JPH0925560A - Vacuum deposition equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] Vacuum film formation that can form a good quality thin film by completely removing the gas generated from the film before the thin film application part and not affecting the thin film application part. Get the device. [Structure] A film unwinding unit, a thin film applying unit, and a film winding unit are installed in one vacuum tank, and a synthetic resin film in a rolled-up state is unwound and placed on the film. In a roll-to-roll type vacuum film forming apparatus for applying a thin film and winding again into a roll, a film pretreatment section 15 is provided between a film unwinding section and a thin film application section, and a film pretreatment section is provided. Reference numeral 15 is a film heating means 14 for heating the film 26 passing through the compartment.
And an exhaust means 17 for performing vacuum exhaust independently of the entire vacuum chamber 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll-to-roll method for applying a thin film by a thin film applying means such as a sputtering method, a vapor deposition method or a CVD method while continuously conveying a long synthetic resin film in a vacuum. Type vacuum film forming apparatus.

[0002]

2. Description of the Related Art Conventionally, in a vacuum film forming apparatus, in order to reach a desired vacuum region from atmospheric pressure in the shortest possible time, or to reduce the gas released from the inside of the vacuum chamber, the contents of the vacuum chamber are reduced. It is common to make the product small.

In a roll-to-roll type vacuum film forming apparatus, a film roll to be processed is set on the unwinding part in a vacuum tank, and while the film is released, it is continuously conveyed to a thin film applying part to apply a thin film. It is a device for applying a thin film on the surface of the film in the winding section and winding it in the winding section. Therefore, in the roll-to-roll type vacuum film forming apparatus, the mechanism such as the film unwinding part, the thin film applying part, and the winding part has been contrived to be compact in one vacuum chamber.

On the other hand, in recent years, in a vacuum film forming apparatus, efforts have been made to form a film in a vacuum chamber as clean as possible in order to obtain a good quality thin film. That is, in the vacuum chamber, generation of gas and particles that adversely affect film formation is suppressed as much as possible, and high-purity materials and gases used for film formation are used to obtain a high-quality thin film without impurities. It is something to try.

The cause of polluting the inside of the vacuum chamber is the presence of gas generated from the inner surface of the vacuum chamber and the inside of the material of the apparatus, the presence of particles scattered outside the intended place at the time of applying the thin film, and the film which is the base of film formation. There are many causes such as the existence of gas generated from the above, and various measures have been taken to improve the cleanliness inside the vacuum chamber.

As a measure for improving the cleanliness inside the vacuum chamber, for example, for the gas generated from the inner surface of the vacuum chamber and the inside of the material of the apparatus, the inner surface of the vacuum chamber is narrowed by making the vacuum chamber small. At the same time, as the material used in the vacuum chamber, materials such as stainless steel, aluminum, and oxygen-free copper, which generate little gas, are being used. In addition, in order to prevent the particles scattered during the thin film deposition from contaminating the inside of the vacuum chamber, devise the material of the deposition preventive plate and the surface treatment method to ensure that the particles scattered outside the intended location are captured. I have to. In addition to these, various measures are taken.

[0007]

The film roll used in the roll-to-roll type vacuum film forming apparatus is produced in the air and is wound into a roll. Therefore, air is present between the layers of the film wound into a roll, and moisture is attached or adsorbed on the surface and inside of the film. The amount of air between the film layers changes depending on the winding tension, and the amount of water attached to or adsorbed on the film changes depending on the temperature and humidity of the winding portion.

When the film roll is released in a vacuum, that is, when the film is unwound from the roll, the air between the film layers diffuses into the vacuum chamber at the same time when the film is released. On the other hand, the water adhering to the film surface or adsorbed internally is gradually gasified during vacuum conveyance and diffuses into the vacuum chamber. In particular, the water adsorbed inside the film is gasified by the water adhering to the film surface, and then diffused from the inside to the surface to be gasified.
take time.

Generally, in a vacuum film forming apparatus, the vacuum chamber is made small. That is, the unwinding part, the thin film applying part, the winding part, etc. are installed close to each other in one vacuum chamber. For this reason, the gas generated from the film and diffused in the vacuum chamber changes the gas atmosphere required for film formation in the thin film deposition section, which makes it impossible to form a high-quality film. Also,
If the water adhering to the film surface or adsorbed inside the film is not completely removed and is supplied to the thin film deposition section while remaining, the thin film is deposited on it, which may affect the film quality. .

The air between the film layers diffuses into the vacuum chamber at the same time when the film is released. Therefore, by providing a partition wall between the unwinding part and the thin film applying part, or by increasing the exhaust capacity of the vacuum pump, it is possible to relatively easily remove the air before it diffuses to the thin film applying part. . However, it has heretofore been difficult to completely remove the moisture attached to the film surface or adsorbed inside the film in a short time. As described above, in the roll-to-roll type vacuum film forming apparatus, the effect of the gas generated from the base film is extremely large, and the complete removal of this gas improves the cleanliness in the vacuum chamber and reduces the thin film. Is a major issue in improving the quality of.

For example, FIG. 2 shows a conventional vacuum film forming apparatus having such a problem. In the figure, 1 is a vacuum tank, 2 is a winding roll as a winding unit, and 3 is a winding roll as a winding unit. Further, 4 is a cooling roll, 5 is a thin film applying unit, 6 is a gas supply unit, and the thin film applying unit is constituted by these. Reference numerals 7a and 7b are vacuum pumps, 8 is a partition wall that suppresses the circulation of the atmosphere between the thin film applying portion side and the unwinding portion and the winding portion side, and 9a and 9b are film passage slits provided in the partition wall 8. 10 is a film.

In the conventional apparatus shown in FIG. 2, the film roll set on the unwinding roll 2 is continuously released at a constant speed and supplied to the thin film applying section. The film 10 supplied from the unwinding unit is wound on the winding roll 3 after applying a thin film on the cooling roll. Mechanisms such as an unwinding unit, a thin film applying unit, and a winding unit are housed in one vacuum chamber 1 as compactly as possible.

In such a vacuum film forming apparatus, a film roll is set at the unwinding portion in the vacuum chamber and vacuum exhaust is performed, and when a certain degree of vacuum is reached, the film is continuously released while applying a thin film. A thin film is applied in the part. When the film is released at the unwinding portion, the air between the film layers and the moisture adsorbed on the film surface and inside are gasified and diffused into the vacuum chamber. The air between the film layers diffuses into the vacuum chamber at the same time when the film is released, but the moisture adhering to the film surface gradually diffuses. The water adsorbed inside the film requires more time because the water adhering to the surface diffuses to the surface after gasification and is gasified.

These gases are exhausted by a vacuum pump, but some of them reattach to the inner wall of the vacuum chamber or the film roll,
When the unwinding part and the thin film applying part are close to each other, the gas diffuses to the thin film applying part.

The thin film applying unit supplies the high-purity gas required for applying the thin film from the gas supply unit 6 with high precision, and the thin film applying unit 5 allows the thin film to be formed on the surface of the film continuously running on the cooling roll. However, at this time, when the air between the film layers and the moisture gasified from the film surface and inside diffuses to the thin film application part, the composition and amount of the gas required for film formation change, and the quality is improved. Be adversely affected.

Further, the moisture adhering to the film surface and the moisture adsorbed internally are gasified and exhausted in a vacuum, but it is difficult to gasify and exhaust all of them in a short time. In particular, it takes time for the moisture adsorbed inside the film to be gasified and exhausted. Therefore, generally, in a vacuum film forming apparatus in which the distance between the unwinding part and the thin film applying part is short, the water adhering to the film surface or the water adsorbed inside the film is supplied to the thin film applying part while remaining in the film, and the thin film applying part By gasifying or forming a thin film on the film with moisture remaining,
The quality is adversely affected.

In order to prevent the gas generated from the unwinding part or the film being conveyed from diffusing to the thin film applying part, the unwinding part side and the thin film applying part side are arranged in the conventional apparatus of FIG. The partitioning method is performed by the partition wall 8. The provision of the partition wall 8 has the effect of suppressing the diffusion of the air between the film layers to the thin film applying portion, but the moisture attached to the film surface or adsorbed internally is not gasified before the partition wall. There is no effect without it. In other words, the water adhering to the film surface or adsorbed internally is supplied to the thin film applying section together with the film.

The present invention solves the problems of the prior art by completely removing the gas generated from the film in the stage before the thin film applying portion so as not to affect the thin film applying portion. An object is to obtain a vacuum film forming apparatus capable of forming a film.

[0019]

According to the vacuum film forming apparatus of the present invention, a film unwinding unit, a thin film applying unit, and a film winding unit are installed in one vacuum chamber and wound into a roll. In a roll-to-roll type vacuum film forming apparatus that unwinds a film of the synthetic resin in the state of being applied, applies a thin film on the film, and takes up the film again in a roll shape, with a film unwinding unit and a thin film applying unit. A film pretreatment section is provided between the film pretreatment sections, and the film pretreatment section is provided with a film heating means for heating the film passing through the section and an exhaust means for performing vacuum evacuation independently of the entire vacuum tank. It is characterized by that.

In the roll-to-roll type vacuum film forming apparatus according to this, the water adhering to the film surface to which a thin film is applied or the water adsorbed inside is efficiently gasified,
Further, the gasified water can be exhausted so as not to reattach to the entire vacuum chamber or the film roll itself.

At that time, as the film heating means of the film pretreatment section, the device is simple and inexpensive,
From the viewpoint of productivity, it is preferable to use an IR heater that heats the film with infrared rays. Alternatively, it is also possible to use a heating roll in which the film is heated by a roll that comes into contact with the film. Further, it is also possible to heat the partition walls of the film pretreatment section.
In that case, there is a method of heating the partition wall with an electric heater, or a method of heating the partition wall with a jacket structure through a heating medium. Further, as the exhaust means of the film pretreatment section, it is preferable to use a cryopump having a high exhaust capacity for water as the main vacuum pump.

[0022]

1 shows an example of the structure of a vacuum film forming apparatus according to the present invention. In FIG. 1, 11 is a vacuum chamber, 12
Is a take-up roll as a take-up unit, 13 is a take-up roll as a take-up unit, 14 is a film heating means (IR heater), 15 is a film pretreatment section in which the heating means is installed, and 16 is a film pretreatment. The heating means for heating the partition walls of the compartment 15 is a vacuum pump (cryopump) 17 for the film pretreatment compartment 15, and 18a and 18b are slits provided in the film pretreatment compartment 15 for passing the film. 19 is a cooling roll, 20 is a thin film applying means, 2
Reference numeral 1 is a gas supply unit, and the thin film deposition unit is constituted by these. Reference numeral 22 is a partition in the vacuum chamber, 23a to 23d are guide rolls, 24a and 24b are slits for film passage provided in the partition 22, 25a and 25b are vacuum pumps, and 26 is a film. The side of the unwinding roll 12 that is separated by the partition wall 22 in the vacuum chamber 11 is called a film chamber 30. The side on which the thin film deposition unit is provided is called the film forming chamber 31. Film chamber 30 and film deposition chamber 3
1 is evacuated by a vacuum pump 25a and a vacuum pump 25b, respectively.

The air between the film layers of the unwinding roll 12 immediately diffuses into the film chamber 30 when the film 26 is unwound. Since the film chamber 30 is separated from the film forming chamber 31 by the partition wall 22, the air diffused in the film chamber 30 is exhausted by the vacuum pump 25b without being diffused in the film forming chamber 31.

The moisture adhering to the surface of the film 26 or adsorbed inside the film 26 is preliminarily treated in the film chamber 30 in the process of the film 26 from the film unwinding portion to the thin film applying portion. When passing through the compartment 15, the film heating means 14 heats the film surface to be gasified. that time,
When the heating means 14 is arranged so as to heat the film from both sides, it can be gasified more efficiently than heating from one side. When the film 26 is heated by the heating means 14, if the film temperature is set below the glass transition temperature,
It can be heated without changing the physical properties of the film.

The gasified moisture is stored in the entire vacuum chamber 1
The film pretreatment section 15 independent of the evacuation system of No. 1
It is evacuated by a vacuum pump that evacuates. As a result, it is possible to prevent the gasified water from being diffused and reattached to the inside of the vacuum chamber 11 or the film roll.

As the vacuum pump 17 used for exhausting the film pretreatment section 15, it is preferable to use a cryopump having a high exhaust capacity for water. Note that gasified moisture may redeposit on the inner surface of the film pretreatment section 15. Therefore, if the film pretreatment section 15 itself is heated, the gasified water can be exhausted without being reattached to the inner surface of the film pretreatment section 15.

As described above, the moisture adhering to the surface of the film 26 or adsorbing the moisture inside the film 26 is removed by the film pretreatment section 15.
It is gasified inside and exhausted. Therefore, even if the film that has passed through the film pretreatment section 15 is supplied into the film forming chamber 31, there is almost no gas generation from the film. As described above, by using the apparatus of the present invention, the air between the film layers or the film surface adhesion, the gas generated by the moisture of the internal adsorption, the thin film applying portion is not affected, a good quality thin film Can be granted.

In FIG. 3, a heating roll 41 is used as a film heating means instead of the IR heater shown in the structural example of FIG.
Shows the case of using. By installing two heating rolls 41 in the film pretreatment section 15, it is possible to heat gas from both sides of the film and efficiently vaporize the water adhering to the surface of the film or adsorbed inside. If the effect is insufficient with two heating rolls, it is possible to deal with it by increasing the number of heating rolls.

[0029]

EXAMPLES AND COMPARATIVE EXAMPLES A PET film of 75 μm thickness, 150 mm width and 25 m rolls wound on a 3-inch aluminum core was used, the apparatus of FIG. 1 was used as an example, and the apparatus of FIG. 2 was used as a comparative example. The film was rewound from the unwinding portion to the winding portion in vacuum, and the weight before and after the rewinding was measured.

Furthermore, after rewinding in a vacuum, the film was rewound gently in the atmosphere so that hot air could pass therethrough, and allowed to stand in a dryer at 120 ° C. for 48 hours, after which it was weighed (including the aluminum core). ) Was measured. By this, the weight of the state without the adhered or adsorbed substance was confirmed. By comparing this weight with the weight before the rewinding treatment and the weight after the rewinding treatment, the gasification amounts of the deposits or adsorbates on the film were compared.

The film before vacuum treatment was at 25 ° C. and 6
The one stored in an atmosphere of 0% RH was used. The rewinding was started at a vacuum rate of 0.5 mPa in the vacuum chamber and a conveying speed of 30 cm / min. The IR heater in FIG. 1 was set so that the film surface temperature was 100 ° C.

As a result, in the case of using the apparatus of FIG. 1 as an example, the weight before the rewinding treatment was 395.2 g, the weight after the rewinding treatment was 394.4 g, and it was left in a dryer at 120 ° C. for 48 hours. The subsequent weight was 394.3 g. That is, in the apparatus of the present invention, it was confirmed that about 90% of the deposit or adsorbate on the film was gasified and exhausted.

On the other hand, in the case of using the apparatus of FIG. 2 as a comparative example, the weight before the rewinding treatment was 395.6 g, the weight after the rewinding treatment was 395.1 g, and the weight was left in a dryer at 120 ° C. for 48 hours. The weight was 394.7 g. That is, in the case of the conventional device, about 5 or about 5
Only 5% could be gasified and exhausted.

[0034]

With the apparatus of the present invention, the water adhering to the film surface or adsorbed inside the film can be efficiently gasified before the film is applied onto the film, and the gas is applied to the film applying section. It is possible to prevent the gas atmosphere of the thin film application part from diffusing up to a change and to prevent the residual water in the film from adversely affecting the applied thin film.
A good quality thin film can be obtained.

[Brief description of drawings]

FIG. 1 is an example of a device configuration according to the present invention (when an IR heater is used).

FIG. 2 Example of conventional device configuration

FIG. 3 is a device configuration example according to the present invention (when a heating roll is used).

[Explanation of symbols]

 1 Vacuum Tank 2 Unwinding Roll 3 Winding Roll 4 Cooling Roll 5 Thin Film Applying Means 6 Gas Supply Section 7a, 7b Vacuum Pump 8 Partitions 9a, 9b Film Passing Slit 10 Film 11 Vacuum Tank 12 Unwinding Roll 13 Winding Roll 14 Film heating means (IR heater) 15 Film pretreatment section 16 Heating means 17 Vacuum pump 18a, 18b Film passing slit 19 Cooling roll 20 Thin film applying means 21 Gas supply part 22 Vacuum tank inner partition wall 23a-23d Guide roll 24a, 24b Film Passing slits 25a, 25b Vacuum pump 26 Film 30 Film chamber 31 Film forming chamber 41 Film heating means (heating roll)

Claims (4)

[Claims] 1. A film unwinding unit, a thin film applying unit, and a film winding unit are installed in a single vacuum chamber, and a film of synthetic resin in a rolled state is unwound.
In a roll-to-roll type vacuum film forming apparatus that applies a thin film on the film and winds it into a roll again, a film pretreatment section is provided between the film unwinding part and the thin film applying part, and the film pretreatment is performed. A vacuum film forming apparatus characterized in that the processing section is provided with a film heating means for heating a film passing through the inside of the section and an evacuation means for evacuation independently of the entire vacuum chamber. 2. The vacuum film forming apparatus according to claim 1, wherein the film heating means in the film pretreatment section is an IR heater for heating the film by infrared rays. 3. The vacuum film forming apparatus according to claim 1, wherein the film heating means in the film pretreatment section is a heating roll for heating the film by a roll that is in contact with the film. 4. The vacuum film forming apparatus according to claim 1, wherein the evacuation means of the film pretreatment section uses a cryopump as a main vacuum pump.